Volcanologist Reveals Deep Earth Secrets

Science creators gain insight into the SciShow production process by joining the team for summer residencies, a role Denali Kincaid held this summer while focusing on geological topics. This program allows residents to work directly with the SciShow team, gaining valuable insight into the scriptwriting and hosting process.

Kincaid dedicated the summer to exploring diverse geological topics, contributing to the show's science communication efforts. The residency aims to bridge the gap between scientific expertise and public understanding through engaging content.

Denali Kincaid highlighted that geology is frequently underestimated despite its pervasive influence on all aspects of life. Kincaid explained that many minerals found on Earth could not exist without the presence of biological life.

For instance, certain rock formations necessitate atmospheric oxygen, which is produced by plants. This illustrates a fundamental, often overlooked, connection between the planet's geological processes and its living systems.

Volcanoes possess the capability to generate localized weather phenomena, including small, tornado-like structures referred to as 'fire whirls'. These occur when a funnel forms over a lava flow, often picking up and scattering hot ash.

Denali Kincaid clarified that these fire whirls are distinct from tornadoes that might independently intersect with a volcanic area. The intense heat from the lava flow directly contributes to their formation.

Disaster movies often sensationalize such natural occurrences, presenting exaggerated scenarios for dramatic effect that do not accurately reflect the typical behavior of these volcano-induced systems.

Lava thickness increases alongside silica levels, as the material traps gases and builds pressure; levels of 60 to 80% silica characterize the most explosive volcanoes compared to the lower volatility of 50% silica lava. Conversely, lava with a silica content around 50% tends to be less explosive or even non-explosive.

Silica acts as a thickening agent, increasing the viscosity of the lava. This thicker consistency traps gases within the magma, allowing pressure to build up significantly before an eruption, which then becomes more violent. Gases 'exalt' from the lava as it transitions from a dissolved component to a gaseous state, further contributing to pressure.

Raw volcanic rock and freshly deposited ash are not immediately suitable for agriculture due to their initial composition. However, these materials are rich in essential plant nutrients such as magnesium and phosphorus.

Over an extended period, volcanic materials break down and transform into highly fertile sediment and soil. This nutrient-rich soil is a significant factor contributing to why human populations continue to reside in close proximity to active volcanoes, despite the inherent risks.

Glacial ice exerts immense weight and pressure on the Earth's crust, effectively suppressing the ascent of molten rock to the surface. The removal of this significant glacial weight, through melting, reduces the confining pressure on the crust.

This reduction in pressure can physically stimulate the generation of more molten material in the mantle, not merely make it easier for existing melt to reach the surface. Historical data from Iceland, for example, indicates a substantial increase in volcanic eruptions—up to a hundredfold—following periods of rapid deglaciation.

Although current climate-induced melting is occurring at a slower pace compared to some past geological events, the phenomenon highlights a critical feedback loop between Earth's climate and its internal geological processes.

The concept suggests that significant pressure changes on the seafloor could potentially trigger an increase in underwater eruptions.

However, this area of research is still relatively nascent and rapidly developing within the geological community. Scientists are actively exploring the theoretical frameworks and gathering data to better understand these potential interactions.

The complex interplay of oceanic pressure and crustal dynamics makes predicting the exact mechanisms and extent of this influence a challenging but crucial field of study.

Falling onto this crust would result in death primarily from impact rather than immediate submersion.

A rare exception is carbonatite lava, which is carbon-based rather than silica-based. This type of lava has a significantly lower temperature and a more liquid consistency, resembling a 'black soup,' into which an object could actually sink.

However, carbonatite lava does not emit the characteristic glow seen in movies. Cinematic portrayals of splashing, molten lava are generally unrealistic for standard volcanic scenarios, often exaggerating the visual effects for dramatic impact.

If a person were to fall into a basaltic lava flow, they would not sink into the molten rock. The primary cause of death in such a scenario would be burning due to the extreme temperatures.

In addition to the heat, the inhalation of volcanic gases could lead to unconsciousness. This effect, though grim, would likely be considered a mercy in such a dire situation, as stated by Denali Kincaid.

The expert’s advisor’s advisor was among those who identified mid-ocean ridges, confirming that many people alive today existed in a time when the scientific community was unaware of these fundamental geographical features. Academic genealogy tracks the mentorship lineage of researchers, illustrating the recentness of this scientific breakthrough.

Many individuals currently alive were born into a world where the scientific community was unaware of the existence of these massive underwater mountain ranges. Denali Kincaid's own advisor's advisor was among the pioneering researchers involved in the discovery of mid-ocean ridges, highlighting how new this field is.

Humanity lacks the control to manage the size or outcome of a triggered eruption, and the energy required to meaningfully dent the pressure of massive volcanic systems remains astronomical. The sheer scale and energy involved in massive volcanic systems are often underestimated, making any human intervention to meaningfully alter their pressure virtually impossible.

Magma frequently originates deep within the Earth's mantle, meaning that a single eruption does not necessarily alleviate pressure for subsequent events. Furthermore, humanity currently lacks the technological capability to control the size or specific outcome of any artificially induced eruption.

Even geothermal power plants, which harness volcanic heat, cannot extract enough energy from systems like Yellowstone to prevent a potential eruption. The amount of heat removed is negligible compared to the colossal energy reserves of such volcanoes.

If magma cools beneath the crust, it becomes plutonic rock, but the material is classified as lava once it reaches the surface. Molten rock is only classified as lava once it reaches the Earth's surface.

If the molten material cools and solidifies beneath the crust, it is known as magma, and the resulting rock is referred to as plutonic rock.

When MORB erupts onto the seafloor, its outermost layer rapidly cools and quenches, forming a layer of volcanic glass.

This basaltic glass is distinct from obsidian, which is a high-silica volcanic glass. Fresh samples of MORB often exhibit an iridescent quality, known as opalescence, which can be attributed to its unique cooling properties or the presence of trace minerals like pyrite.

Geochemists prefer to collect and study these glass samples because they offer a pristine record of the mantle's composition. Glass avoids the chemical alteration that can occur when molten rock interacts with seawater, which would contaminate its geochemical signature.

Mid-ocean ridges are crucial research sites for geochemists because they provide the purest samples of the Earth's mantle material. These underwater mountain ranges are where tectonic plates diverge, allowing molten material to rise directly from the mantle.

Unlike continental volcanoes, where magma must pass through and interact with various crustal materials, mid-ocean ridges offer an unfiltered view of the mantle's actual composition. The interaction with crustal rock on continents inevitably alters the geochemistry of the magma, making it less representative of its deep-earth origin.

By studying the pristine molten material at mid-ocean ridges, scientists can gain accurate insights into the fundamental composition and processes occurring within the Earth's interior.

Seawater often becomes trapped and circulates within the distinct, pillow-shaped lava structures that emerge when magma erupts on the ocean floor. As molten lava encounters cold seawater, its outer surface rapidly cools and solidifies, while the interior remains molten and continues to flow, pushing outwards to create these characteristic shapes.

Occasionally, seawater can become trapped within these lava pillows, circulating through their internal structures. This interaction with water plays a significant role in their formation and contributes to the unique morphology observed in submarine volcanic environments.

Denali Kincaid reviewed a recent television show that featured highly unrealistic depictions of underwater volcanoes, particularly concerning the behavior of lava. The show's CGI portrayed lava flowing in liquid rivers across the ocean floor, which is scientifically inaccurate.

Lava cannot flow in extended liquid rivers underwater because contact with water instantly quenches it, causing it to solidify rapidly. This immediate cooling process prevents the sustained flow seen in the show.

Underwater volcanic eruptions are generally far less visually dramatic than their terrestrial counterparts. The immense pressure and cooling effect of seawater mean there is typically no exposed molten material to create the spectacular displays often associated with volcanoes on land.

Kincaid described the portrayal as "the least scientifically accurate thing I've ever seen in my whole life," emphasizing the significant liberties taken with scientific reality for entertainment purposes.

The television show also presented significant biological inaccuracies regarding crinoids, portraying them as dangerous, human-eating creatures. This depiction is contrary to the actual biology of crinoids, which are marine animals related to starfish and exhibit radial symmetry.

Denali Kincaid shared a personal anecdote, expressing surprise upon seeing a live crinoid from a submersible. Having only encountered crinoids in academic contexts as fossils, the encounter with a living specimen was a novel experience, highlighting a common misconception about these ancient marine invertebrates.

Denali Kincaid is active on several social media platforms, including Instagram, TikTok, and YouTube, where she can be found under the username 'Dykenite.' This username is a geological reference, referring to an igneous intrusion.